Trent Williams missed practice, while Christian McCaffrey was full participant

The 49ers played last week without left tackle Trent Williams (ankle) and receiver Deebo Samuel (shoulder). They will play this week without Samuel, who is out at least two weeks with a hairline fracture.Williams remained out of practice Wednesday, but the 49ers hope to get him back on the field Thursday.Quarterback Brock Purdy (concussion) was the only other player who missed Wednesday's practice with an injury. He began having concussion symptoms on the way home. "We finally found that out when we landed," coach Kyle Shanahan said Wednesday. "We were all pretty asleep, but then he got all checked up yesterday, and now he's in the protocol."This season, no player has returned from concussion protocol to play the following week, so it's likely Sam Bradford will start against the Bengals.The good news for the 49ers is running back Christian McCaffrey (oblique) returned to full work Wednesday. Linebacker Dre Greenlaw took a veteran rest day.